The link between PCOS and insulin resistance
This September is PCOS awareness month. PCOS -polycystic ovarian syndrome -is a cluster of symptoms found in approximately 1 in 5 women. It is associated with irregular periods, potentially reduced fertility, acne and excess body hair.
PCOS and insulin resistance
Some 70% of people with PCOS also have insulin resistance (1). This insulin resistance is one of the reasons why PCOS is associated with people of a larger body, and difficulty with intention weight loss. Insulin is a hormone that that regulates glucose sugar in the blood to be used for immediate energy or stored. After eating, insulin levels rise in response to blood glucose rising, with both glucose and insulin falling after this. When insulin resistance occurs, the body becomes inefficient at using insulin to manage even normal levels of glucose. With resistance, a higher amount of circulating insulin is required to have the same effect. Insulin resistance is commonly associated with type 2 diabetes.
In PCOS, high levels of insulin the the body delivers more insulin to the ovaries. The ovaries respond to this by producing higher levels of testosterone, a male hormone (2). In a feedback loop, insulin resistance (or high insulin levels) is both a symptom and driver of PCOS expression. As such, being able to improve insulin sensitivity may help to manage PCOS symptoms. Plus, it can help to reduce the risk of type 2 diabetes later on.
It is important to note, that despite this feedback loop, having PCOS is not your fault.
Both insulin resistance and PCOS are highly individual, so will look different in each person with either or both conditions.
Common symptoms
Insulin resistance can drive cravings for carbohydrate-rich foods. This can lead to a higher intake of food and additional weight gain, which then adds to the strength of insulin resistance and PCOS symptoms. For people with PCOS who are in larger bodies or have strong cravings, this can make advice to eat less and lose weight difficult and frustrating.
Managing PCOS and insulin resistance
In some cases, doctors may prescribe metformin. This is a drug commonly given to people with type 2 diabetes, to support the body's handling of insulin to improve blood sugar levels. However, there are diet and lifestyle tweaks to support management of PCOS and insulin resistance too.
Eating regularly (for example, three main meals with two or three snacks throughout the day) can help to keep bloody sugar levels stable. If you are someone who doesn't eat until you're really hungry, this can help to stop overeating as well. Inclusion of foods with a low GI and source of protein can be helpful for staying full for longer, as these foods take longer to move through the digestive system. Getting plenty of fibre (generally high in low GI foods such as fruit and veg and whole grains), is also important for your overall health too, and can help to lower cholesterol levels.
You may find a moderate carbohydrate intake helpful. This means there is still rooms for fibre and the variety of micronutrients in carbohydrates, such as B vitamins in cereal grains and beta carotene in orange and green veg. Plus, carbohydrates are filling and satisfying, so you shouldn't have to cut them out if you enjoy them. By reducing carbohydrates from a high to moderate part of your day, the impact insulin resistance can be lessened.
Exercise can also help. Higher intensity sessions may have the strongest impact of insulin resistance and can be done in a short time frame. However, they can also increase cortisol -the stress hormone -so be cautious of doing these sessions too often or for too long. Too much cortisol can actually increase insulin resistance, so finding a balance is important. More moderate intensity cardio exercise such as walking, swimming and cycling are also good options.
UK guidelines recommend strength (resistance) training twice a week (3). This can include weights, resistance bands or simply body weight. Resistance training supports bone mass density, and building muscle can increase your daily energy expenditure, even when at rest.
Finally, don't forget to rest! This includes active recovery, but also just letting yourself be still. Time spent on the sofa is a-ok. Although some yoga classes can be quite intense and will count towards your resistance training quota, a slower Hatha class or restorative session can be a really nice way to unwind. It's a great way to stop cortisol levels sneaking up, and is good for mobility too!
As insulin is reduced, the body has less of a drive towards producing high androgen hormones, helping to relieve symptoms of PCOS.
References
- DeUgarte et al. 2005. Prevalence of insulin resistance in the polycystic ovary syndrome using the homeostasis model assessment.
- Conway. 2016. Polycystic ovary syndrome. (book).
- UK exercise guidelines. https://www.nhs.uk/live-well/exercise/